I have the same thing... not neccessarily cold but cannot stop shaking/shivering.
My dad pointed out that I may not feel cold but it's my body's reaction to having to give all my heat to bubs, cause bubs gets all my heat, my body has to shiver to produce enough to keep us both warm. Sounds weird but it actually makes sense... I don't feel cold but my body temp may be lower.

Just another option! I know how annoying it is!! And after like 5 mins my back aches soooo much from the shaking...